Do SYEs fit all 231s?

[dmille4.6]

I found a 231 T/C with a SYE and a Tom Woods driveshaft for $250.00. I know this is a steal cause the d/s is more than that but not sure if it will work on mine. I have a 99 TJ 6cl Auto with a RC 4 in lift. The t/c came off of a 94 YJ 6cyl 5 speed with a 4 in lift. Im pretty sure that puts the spline counts at the same (23) but read somewhere there was a long and short input shaft. Will all of this just swap out? if not can i buy the case take out the SYE and put in my case and run the driveshaft? Should be same length right since both were lifted 4 in? I know you know Bounty Hunter! lol already talked to you about a t/c couple weeks ago.

 

[currupt4130]

The SYE will work. They're all the same. For the YJ's they have you press out the bearings from one of the sprockets that rides on the main shaft. The TJ's already do not have the bearings. You should be just fine. The 231 from the YJ might give you trouble if you try to instal the case whole though, the YJs use a vacuum actuator and I don't think they have some of the same shift sensors. Nothing some McGyvering couldn't fix, but I'd go ahead and isntall the SYE in your case.

 

[Bounty__Hunter]

Those two 231's will not interchange, the 4cyl model has a short 21spl input and your 6cyl model has a long 23spl input. You can however swap the SYE over to your 6cyl 231, everything will swap over fine.

If you were closer, I'd make the swap for you in a couple of hours while you waited and learned. Contact me if you have any problems along the way.

 

[dmille4.6]

both are 6 cyl bounty hunter, but i know what your talking about. i got a buddy that has done a sye so im going to try and get him to help me. will i have to press bearings off the old sye in the yj cause i dont have those type of tools. driveshaft length ok? cant go wrong at $250 for everything right?

 

[currupt4130]

both are 6 cyl bounty hunter, but i know what your talking about. i got a buddy that has done a sye so im going to try and get him to help me. will i have to press bearings off the old sye in the yj cause i dont have those type of tools. driveshaft length ok? cant go wrong at $250 for everything right?

You won't have to press any bearings out. The bearings I was referring to are in a transfer case part on the YJs. When they made the 231s for the TJs they went to a solely fluid boundary between the gear and the mainshaft. Nothing gets pressed on or off the main shaft in a TJ when you install the SYE.

 

[dmille4.6]

alright im going to buy it and try it out. thanks

 

[Bounty__Hunter]

Okay, I read it wrong, both are 23spl but are different length input shafts.

Everything will still swap over to your 231 just fine.

It's unlikely the driveshaft will be the correct length as the 5spd and auto trannies are different lengths. But it's pretty cheap to have driveshaft shortened and balanced, runs about $65 around here.

You know you will need adj. upper control arms in the rear to point the pinion at the transfer case once you install the SYE?

 

[dmille4.6]

no i didnt know that. so i have to buy adj upper control arms too? dang that sucks. how much do they run? what if i dont take the transfer case drop bracket out just yet?